THE PLANCK SKY MODEL

Welcome to the PSM website!

The project

The Planck Sky Model (PSM) is a global representation of the
multi-component sky at frequencies ranging from 1 GHz to 1 THz,
although it should in principle be usable from about 400 MHz to
about 3 THz.
It is designed to summarize in a synthetic way as much as
possible of our present knowledge of the GHz sky. It comes with a
complete and versatile set of programs and data,
that can be used for the simulation or the prediction of sky emission
in the frequency range of typical CMB experiments, and in particular
of the Planck sky mission. It has originally been developed as part of the
activities of Planck component separation Working Group (or "Working
Group 2" - WG2), and of the ADAMIS team at APC.

The PSM software is developed with the objective to give users the
opportunity to investigate the model in some depth: look at its
parameters, visualise its predictions for all individual components
in various formats, simulate sky emission compatible with a given
parameter set, observe the modelled sky with a synthetic
instrument. In particular, it makes possible the simulation of
sky emission maps as could be plausibly observed by Planck or other
CMB experiments, that can be used as inputs for the development and testing of data
processing and analysis techniques.

The model has has been developed
mostly by members of the Planck collaboration as a simulation tool
for Planck activities. The first publicly released version (v1/7.8) is "pre-launch",
with no Planck observation used to model sky emission.
There is, hence, no guaranteee that simulated maps obtained
with that version of the PSM will be fully compatible with Planck observations.
Updating the model on the basis of Planck observations is one
of the projects of the Planck collaboration (Project 1.11:
Planck Sky Model ).

The software

The software is developed mostly in the IDL programming language. It uses the HEALPix sky-pixellisation package (with calls to C++ binaries),
the astron and mpfit libraries, and uses CAMB and or CLASS as
Boltzmann codes for computing the harmonic power spectrum of specific CMB
models, as well as for computing the matter power spectrum at
vairous redshifts if needed. The package comes as a collection of component-specific
simulation codes put together by driver routines, automating fastidious tasks like parameter processing and component map coaddition.

The PSM is being continuously developed. Visit the web site regularly for releases of simulation products and of the software package.

Collaborators welcome

We are looking for a
software engineer to help
implementing and consolidating the PSM code.

The PSM is based on interpolation, extrapolation, fusion and interpretation of the best
millimeter and sub-millimeter wave datasets available. Maps of
diffuse observations, and/or catalogues of observed galactic and
extragalactic sources are very useful for developing the
model. The model of diffuse emission is mostly built using Planck,
WMAP, IRAS, and DIRBE space mission data, complemented with the 408-MHz
all sky survey synchrotron map of Haslam et al. (1982) and the CO (J=1-0)
survey of Dame, Hartmann and Thaddeus (2001). Compact sources are
modelled by extrapolating radio surveys (NVSS, SUMSS, GB6, PMN)
and the IRAS catalogue of point sources.
We are interested in any additional data that can be used to help improve
the PSM.

We wish to implement a model of zodiacal light emission
in the PSM. Suggestions, inputs, software and suggestions welcome.

Publications

Download the main paper describing the first version (Pre-Launch) of
the PSM (published in A&A):
aa20019-12_tap.pdf (10 MB)

PSM releases

The following releases of the PSM are available for
download. The status specifies whether the release is RESTRICTED to
the Planck collaboration, or PUBLIC. Check the appropriate release page for
additional information about each particular release: general
comments, limitation and known bugs, specific recommendations.
The PUBLIC releases are made available under the terms of the GNU General Public License as published by
the Free Software Foundation (version 3 of the license, or any later
version at the user option).

The current RECOMMENDED VERSION is v1.8.0 (or v1.7.8 for non
Planck members).

This is a minor update of v1.7.4. A new feature is a model of
galactic magnetic field according to Fauvet et al. 2011, that
can be used to generate templates of polarised galactic emission.
Available instrument models based on Planck RIMOs have been temporarily
modified, but probably need a complete revision.

Version essentially fixing bugs introduced in
version 1.7.3: Corrected dust polarisation amplitude,
fixed bugs for Gaussian CMB (which has been improved and tested more thoroughly). Also expanded the
documentation, implemented relativistic SZ
effect included for some SZ models, and updated the
radio-frequency part of ultra-compact HII regions.